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The power of randomization by sex in multilocus genetic evolution
Liudmyla Vasylenko1, Marcus W Feldman2, Adi Livnat3
1Department of Evolutionary and Environmental Biology and Institute of Evolution, University of Haifa, 199 Aba Khoushy Ave, Haifa, 3498838, Israel.
Biology Direct
|November 23, 2020
Summary
Sexual reproduction randomizes genetic combinations, favoring alleles that perform well across diverse genotypes. This randomization effect strengthens with more genes, supporting mixability theory in complex populations.
Area of Science:
- Evolutionary biology
- Population genetics
Background:
- Sexual reproduction's role in increasing population fitness is debated.
- Mixability theory proposes sex favors alleles performing well across genetic combinations, not just specific high-fitness combinations.
- Previous work established this for single-locus diploid models.
Purpose of the Study:
- To extend mixability theory to multilocus genetic models.
- To investigate the role of sexual recombination in randomizing genetic combinations.
- To compare sexual and asexual reproduction in terms of genetic randomization.
Main Methods:
- Theoretical modeling of haploid and diploid populations.
- Analysis of genetic recombination under sexual and asexual reproduction.
- Multilocus genetic models were employed.
Main Results:
- Sexual recombination's randomization power extends to multilocus cases in both haploids and diploids.
- The randomization effect intensifies with an increasing number of loci.
- Sexual recombination was confirmed as the driver of this randomization effect.
Conclusions:
- The randomization effect of sex under mixability theory is robust and strengthens with genetic complexity.
- Allele performance across existing combinations predicts performance in untested combinations.
- Findings align with theories viewing evolution as a learning process and have implications for understanding adaptation.
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